This invention relates to a self-propelled combine and more particularly to a new overall design and arrangements of components for such a combine.
A conventional modern self-propelled combine includes a rigid main frame mounted on a pair of transversely spaced forward drive wheels and steerable rear wheels. A forward transversely elongated header conventionally removes crop material from the field as the machine advances and the crop material is fed rearwardly through a feederhouse to a threshing and separating mechanism mounted in the main combine frame or body. A cleaning mechanism is conventionally disposed below the separating mechanism and the cleaned grain is delivered to an elevated grain tank that is normally located above the threshing and separating mechanisms. Such combines conventionally have an elevated operator's station, and in most cases an elevated engine. Thus, a typical combine is somewhat top heavy, particularly when the grain tank is loaded, the overall height of the combine also being a disadvantage when storing or shipping the machine.
Combine sizes and capacities have increased dramatically in recent years, and with the increase in capacity, there has been an attendant increase in the size or width of the harvesting header, so that a modern combine is capable of harvesting a relatively wide swath of material as the machine advances. However, because of the design and arrangement of components on current combines, the size of the grain tank has been limited. For example, even among the highest capacity machines currently on the market, a 200-bushel grain tank, even with extensions to increase the capacity of the tank, is considered a large tank, and when a combine is operating in high yielding crops, such as corn that can produce 200 bushels of corn per acre, the combine must have its grain tank unloaded at frequent intervals, delaying the harvesting process. In many cases, the combine grain tank is unloaded into a large truck, such as a semi-trailer, which normally is not driven into the field but is rather parked at the end of the rows, and, particularly in larger fields, it has been found that at times the grain tank capacities are insufficient for the combine to travel the length of the field and back again to the parked truck before the grain tank has had to be unloaded.
Another problem with conventional combine design has been the sensitivity to slopes, the separating and cleaning mechanism being overloaded on the downhill side when operating in a sloping field. Of course, the recently introduced rotary or axial flow combines have reduced the slope sensitivity for the separating mechanism, but the problems with the cleaners have remained when operating on side hills. On severe slopes, the problem has been overcome by providing hillside combines at significantly increased cost for a given combine capacity, and there is also currently available a sidehill combine that is capable of maintaining a level stance on more moderate side hill slopes, with a somewhat smaller cost penalty than the typical hillside combine.